The IP multimedia subsystem (IMS) network architecture is an example of an end-to-end architecture that enables the delivery of real time multimedia services using IP related technologies. It merges Internet, fixed wireline telephony and cellular capabilities. It manages different access related constraints imposed by heterogeneous access technologies such handover and roaming between different networks in radio access networks and supports many kinds of equipment. There is an expanding need to provide application-to-application communication among a growing variety of applications over networks that support a variety of communications technologies such as, text based chat, photo/video/music/file transfer, live video sharing, group chat, location sharing or any kind of 2-way or group communications, for example. The present invention meets this need.